Safety appliance for steam jet refrigeration apparatus



Patented Jan. 18, 1938 SAFETY APPLIANCE non STEAM .m'r ne- FBIGERATION APPARATUS ration, New York, N.

E, a corporation of Vir- Application .liune 19, 1934, Serial No. 731,389

This invention relates to steam jet reiriger tion apparatus and an object oi the present inm stion, may be subjected to the building up therein of excessive pressure sumcient to burst the tank should its companion mechanism, especial ly the automatically operated control valves, fail to function properly. 7

The present invention comprehends the provision of safety means to prevent bursting of the flash tank, which safety means is in itself free from any automatically operating mechanisms. relying on a column of water or other liquid to 20 control the bleeding of excessive pressure from the flash tank. The liquid is equal in feet of liquid to the difierence between the absolute pressure in the flash tank and the absolute pressure at the end of the column remote from the 25 tank expressed in feet of liquid which provides control of the bleeding of excessive pressure from the flash tank.

With these and other objects in view as may appear from the accompanying specification, the so invention consists of various features of construction and combination of parts, which will be first described in connection with the accom- Pfl ying drawing which shows 2. =4 atic layout of a steam jet refrigerating apparatus 35 having the improved safety appliance attached thereto, and the features forming the invention will be specifically pointed out in the claims. Referring more particularly to the drawing, the steam jet refrigerating apparatus illus- 49 trated may be of any conventional type or layout embodying an evaporator or flash tank of any approved type in which is maintained a predetermined level of water or other liquid as indicated by the dotted line 2. The apparatus in- 45 eludes the primary condenser 3 which is connected to the flash tank 6 by the primary ejector t and to the interand after-cooler 5 by the secondary ejectors 6 and l. The chilled water is pumped from the evaporator or flash tank l m by the chilled water pump 8 and is delivered through the discharge pipe t to any suitable type of cooling system.

A pipe it opens into the flash tank or evaporater i above the water level therein and the 55 lower end of the pipe It opens out into a reservoir It. The reservoir H has a predetermined quantity of liquid such as water or the like therein and, as clearly shown in the drawing, the pipe Ill projects below the liquid level in the reservoir. An overflow pipe I2 is connected to the reservoir above the normal liquid level therein and may be connected to a sewer or to any other suitable outlet.

When the flash tank or evaporator l, is not in operation, there will be no water or liquid in the down-pipe ID, as any liquid therein will pass into the reservoir 1 I. Of course the lower end of the down-pipe will have water or other liquid therein to a height equal to the depth of insertion of the pipe Hi into the liquid in the reservoir. As soon as the steam jet refrigerating apparatus is placed in operation the vacuum maintained in the flash tank I will lift water or liquid from the reservoir ll upwardly in the pipe It, until the liquid reaches a height in the down-pipe equal to the pressure expressed in feet of liquid between the absolute pressure carried in the flash tank, and the absolute pressure in the reservoir H, which in most cases is atmospheric pressure.

Should the pressure rise in the flash tank, such increasing pressure acting on the liquid column in the pipe Ill, will force the liquid downwardly and into the reservoir ii. If the pressure in the tank i becomes so great as to be dangerous. such pressure, acting through the pipe It will force the liquid in the reservoir Ii upwardly and out through the overflow pipe 12 providing a bleed-0E for the pressure from the evaporator or flash tank l, and preventing any liability of bursting of such tank.

If it is so desired a liquid or make-up water supply line as indicated at It may be provided for refilling the reservoir it.

It will be understood that the invention is not to be limited to the specific construction or arrangement of parts shown but that they may be widely modified within the invention defined by the claims.

What is claimed is:

1. In a steam jet refrigeration system, the combination with a flash tank having a normal water level therein, of a safety bleed-oil pipe connected to said tank above the normal water level in the tank, a reservoir, said pipe opening into said reservoir, said reservoir having aquantity of liquid therein to build up a back pressure in said pipe.

2. In a steam jet refrigeration system, the combination with a flash tank having a normal water level therein, of a safety mead-or pipe connected to said tank above the normal water level in the tank, a reservoir. said pipecpening into said reservoir, saidreservoir having a quantity oi liquid therein to build. up a back preasurein:

said pipe, and an overflow pipe connected to said reservoir above .the normal liquid level 3. In a steam jet refrigeration system, the combination with a flash tank having a normal water level therein, oi a safety bleed-oi! pipe connected to said tank above the normal water level in the tank. a reservoir at the outlet end of said pipe and having liquid therein, said pipe being oi such length that the normal pressure difference between the interior oi the flash tank and the interior oi the reservoir will raise a column oi water in the pipe a height equal in feet oi water to, the diiierence between the absolute pressure in the flash tank and the absolute pressure in the reservoir, whereby when said absolute pressure difference is reversed pressure will bleed from said flash tank to said reservoir.

4. In a steam jet refrigeration system, the

, combination with a flash tank having a normal water level therein, 01' a safety bleed-oft pipe connected to said tank above the normal water" aromas solute pressure in the flash tank and the absolute pressure in the reservoir, whereby when said absolute pressure difl'erence is reversed pressure will bleed from said flash tank to said reservoir, and an overflow connected to said reservoir above the normal liquid level therein.

'5. In a saiety appliance ior steam jet. reirigeration systems including a flash tank, a safety bleed-oil pipe connected to said tank above the normal water level therein, a reservoir, said pipe opening into said reservoir, said reservoir having a quantity of liquid therein to build up a pipe being oi such length that the normal pres-' sure diiierence' between the interior of the flash tank and the interior oi the reservoir will raise a column of water in the pipe a height equal in feet of water to the diiierence between the absolute pressure in the flash tank and the absolute pressure in the reservoir, whereby when said absolute pressure difl'erence is reversed pressure will bleed from said flash tank to said reservoir,

and an overflow connected to said reservoir above the normal liquid level therein whereby a seal will be maintained through said bleed oil pipe to said flash tank at all times.

BARTLEY R. MCBATH, JR. 

